:root {
  --bg-primary: #0a0e1a;
  --bg-secondary: #121829;
  --bg-card: #1a2238;
  --bg-card-hover: #242d47;
  --text-primary: #ffffff;
  --text-secondary: #a0aec0;
  --accent-gold: #f59e0b;
  --accent-gold-light: #fbbf24;
  --accent-blue: #3b82f6;
  --accent-red: #ef4444;
  --accent-green: #22c55e;
  --border: rgba(245, 158, 11, 0.18);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft JhengHei", sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.6;
}

a { color: var(--accent-gold-light); text-decoration: none; }

.container { max-width: 1100px; margin: 0 auto; padding: 24px 20px; }

/* 頂欄 */
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 24px; background: var(--bg-secondary);
  border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 10;
}
.topbar .brand { font-weight: 700; font-size: 18px; color: var(--accent-gold-light); }
.topbar .user-area { display: flex; align-items: center; gap: 14px; font-size: 14px; color: var(--text-secondary); }
.btn {
  display: inline-block; border: none; cursor: pointer;
  background: linear-gradient(135deg, var(--accent-gold), #d97706);
  color: #1a1305; font-weight: 600; padding: 10px 22px; border-radius: 8px; font-size: 14px;
  transition: transform .15s, filter .15s;
}
.btn:hover { filter: brightness(1.1); transform: translateY(-1px); }
.btn.secondary { background: var(--bg-card); color: var(--text-primary); border: 1px solid var(--border); }
.btn.danger { background: transparent; color: var(--accent-red); border: 1px solid rgba(239,68,68,.4); padding: 6px 12px; }
.btn.small { padding: 6px 14px; font-size: 13px; }
.btn:disabled { opacity: .5; cursor: not-allowed; transform: none; }

/* 登入頁 */
.login-wrap { display: flex; align-items: center; justify-content: center; min-height: 100vh; padding: 20px; }
.login-card {
  width: 100%; max-width: 400px; background: var(--bg-secondary);
  border: 1px solid var(--border); border-radius: 16px; padding: 40px 32px;
}
.login-card h1 { font-size: 22px; margin-bottom: 6px; }
.login-card .sub { color: var(--text-secondary); font-size: 14px; margin-bottom: 28px; }
.field { margin-bottom: 16px; }
.field label { display: block; font-size: 13px; color: var(--text-secondary); margin-bottom: 6px; }
.field input, .field select, .field textarea {
  width: 100%; background: var(--bg-primary); border: 1px solid var(--border);
  border-radius: 8px; padding: 11px 14px; color: var(--text-primary); font-size: 15px;
}
.field input:focus, .field select:focus, .field textarea:focus { outline: none; border-color: var(--accent-gold); }
.btn.block { width: 100%; padding: 12px; margin-top: 8px; }
.error-msg { color: var(--accent-red); font-size: 13px; min-height: 20px; margin: 8px 0; }

/* 課程卡片 */
.page-title { font-size: 24px; margin-bottom: 4px; }
.page-sub { color: var(--text-secondary); font-size: 14px; margin-bottom: 24px; }
.filters { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 24px; }
.chip {
  padding: 7px 18px; border-radius: 999px; font-size: 13px; cursor: pointer;
  background: var(--bg-card); color: var(--text-secondary); border: 1px solid var(--border);
}
.chip.active { background: linear-gradient(135deg, var(--accent-gold), #d97706); color: #1a1305; font-weight: 600; border-color: transparent; }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 18px; }
.card {
  background: var(--bg-card); border: 1px solid var(--border); border-radius: 14px;
  padding: 22px; display: flex; flex-direction: column; gap: 12px;
  transition: transform .15s, background .15s;
}
.card:hover { background: var(--bg-card-hover); transform: translateY(-3px); }
.card h3 { font-size: 17px; }
.card .desc { color: var(--text-secondary); font-size: 14px; flex: 1; }
.badge { font-size: 12px; padding: 3px 10px; border-radius: 999px; width: fit-content; }
.badge.coze { background: rgba(59,130,246,.15); color: #60a5fa; }
.badge.association { background: rgba(245,158,11,.15); color: var(--accent-gold-light); }
.badge.granted { background: rgba(34,197,94,.15); color: var(--accent-green); }
.badge.locked { background: rgba(239,68,68,.12); color: #f87171; }
.card .foot { display: flex; align-items: center; justify-content: space-between; gap: 10px; }

/* 影片頁 */
.player-shell { background: #000; border-radius: 14px; overflow: hidden; border: 1px solid var(--border); }
.player-shell video { width: 100%; display: block; aspect-ratio: 16/9; background: #000; }
.video-meta { margin: 20px 0; }
.video-meta h1 { font-size: 22px; margin-bottom: 8px; }
.notice { background: var(--bg-card); border: 1px solid var(--border); border-radius: 12px; padding: 28px; text-align: center; color: var(--text-secondary); }
.notice .big { font-size: 40px; display: block; margin-bottom: 10px; }

/* 管理後台 */
.tabs { display: flex; gap: 8px; border-bottom: 1px solid var(--border); margin-bottom: 24px; flex-wrap: wrap; }
.tab { padding: 10px 18px; cursor: pointer; color: var(--text-secondary); font-size: 15px; border-bottom: 2px solid transparent; }
.tab.active { color: var(--accent-gold-light); border-bottom-color: var(--accent-gold); font-weight: 600; }
.panel { display: none; }
.panel.active { display: block; }
table { width: 100%; border-collapse: collapse; font-size: 14px; }
th, td { text-align: left; padding: 11px 12px; border-bottom: 1px solid var(--border); }
th { color: var(--text-secondary); font-weight: 500; font-size: 13px; }
.form-row { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 20px; background: var(--bg-card); padding: 18px; border-radius: 12px; border: 1px solid var(--border); }
.form-row .field { margin: 0; flex: 1; min-width: 160px; }
.toast { position: fixed; bottom: 24px; right: 24px; background: var(--bg-card-hover); border: 1px solid var(--border); padding: 12px 20px; border-radius: 10px; font-size: 14px; opacity: 0; transition: opacity .3s; pointer-events: none; }
.toast.show { opacity: 1; }
.empty { color: var(--text-secondary); text-align: center; padding: 40px; }

@media (max-width: 600px) {
  .grid { grid-template-columns: 1fr; }
  .topbar { padding: 14px 16px; }
  .form-row { flex-direction: column; }
}